m45 sub length help

[jnc71106]

hello

im hoping to be having a go at imaging m45 soon would just like to get an idea of sub length and iso setting i should be aiming for as i see people using different settings in most pics

i will be using a guiding setup with my 102mm ed frac with flattener/reducer which takes it down to f/5.6 and my modified 500D dslr

this will be done from a dark site i should add

do i go 10 min at iso 1600 or 5min at iso 1600 or do i go with iso 800 on the shots or do i mix it up

cheers

jake

[nmoushon]

If you have a guiding setup and are in dark skies I would do iso 800 for sure. Just to help with noise. Might have to take a couple extra subs but in my opinion well worth it. And I would also do both 10min and 5min subs. Look at Carastros post here: http://stargazerslounge.com/imaging-deep-sky/165400-m45-pleiades-cluster-27-11-11-a.html

She only did 5min subs at iso 800 and it turned out great! And she took these from the polluted skies near London(i think). So if you do at least the same and in dark skies you'll get a very nice set of images to process.

[Tim]

With a bright star target like M45 you need to be aware of bright reflection artifacts. They can soon build round the brighter stars and start to ruin a picture. So if you can stretch to 10 mins at iso800, have a good look at the image if possible, preferably with a hard stretch applied.

I've had nice results with 15 min subs with my 77mm refractor, but that was with a cooled camera. In the interests of keeping noise down you might find you are better with more shorter subs. The dark sky will help you find the fainter reflection nebulosity too.

cheers

Tim

[Psychobilly]

Looking back to my M45 image from 2008 I used my Megrez72 and FF III (f4.8) and mix of sub lengths of 180S and 240s at ISO800 and ISO1600

I'll go back through my other M45 images and see what settings I used

Peter

[jnc71106]

Thanks for the replies

My hunch was to go with 5 mins @800 will chuck in a few 10 mins as well at the end to see what difference it makes